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Inland Ports
Published in Petros A. Ioannou, Intelligent Freight Transportation, 2008
As defined by the Army Corps of Engineers, inland waterway ports are the original inland port in the United States. Current inland waterway ports handle bulk commodities, including grain, coal, petroleum, and chemicals in addition to general break bulk and containerized cargo. Inland waterways provide the ability to efficiently transport large volumes of bulk commodities over long distances. Individual barges are lashed together to form a “tow.” On smaller waterways tows normally consist of four to six barges. On the larger rivers with locks, such as the Ohio, Upper Mississippi, Illinois, and Tennessee rivers, 15-barge tows are common. Such tows move approximately 22,500 tons of cargo as a single unit. A single 15-barge tow is equivalent to about 225 rail cars or 870 tractor-trailer trucks. Tows can consist of over forty barges on the Mississippi River below its confluence with the Ohio River, well over 50,000 tons of cargo. As a result of this efficiency, inland waterways can enable fuel consumption savings, reduce air pollution, reduce traffic congestion, better transport safety, and lessen noise pollution.3
Planning a Carton or Full-Case Order-Fulfillment Operation
Published in David E. Mulcahy, John P. Dieltz, Order-Fulfillment and Across-the-Dock Concepts, Design, and Operations Handbook, 2003
David E. Mulcahy, John P. Dieltz
The first electric tow tractor is the electric battery-powered walkie tow tractor. The electric battery-powered walkie tow tractor is a vehicle that does not have an operator platform. As an order picker travels through a pick aisle, by walking in the front of the vehicle, the operator steers and maintains tow tractor control.
Investigating the potential of using glass foam for an EMAS material to mitigate aircraft overrun accidents
Published in International Journal of Pavement Engineering, 2021
Aircraft damage within the EMAS is most likely to occur at the nose gear strut since the nose gear strut is designed for low vertical and horizontal loading in comparison to the main gear struts. Significant horizontal force is applied to the nose gear during deceleration as the aircraft decelerates within the EMAS, Figure 21. The maximum drag induced on the nose gear differs by 2.8% between the two materials. The maximum nose gear drag force in the glass foam material is 154.3 kN (34,960 lb) compared to 159.9 kN (35,950 lb) in the cementitious material. These values are used to predict possible nose gear strut damage. A conservative value for the nose gear strut strength is the allowable tow load. The maximum allowable tow load is equal to 0.15 *MCDTW (maximum certificated design taxi weight) (FAR 1970). The B737-900 maximum certificated design taxi weight is 74,600 kg (164,500 lbs). Therefore the maximum allowable towing load is 109,800 N (24,675 lbs). Both material cases result in a maximum drag force that exceeds the maximum towing load. Therefore, further analysis is warranted to determine the suitability of the calculated drag force compared with the actual aircraft nose gear strength. The weak glass foam material within the 0.6–0.9 strain range, Figure 17, results in greater nose tire penetration and oscillating load behaviour. The maximum vertical strut force within the glass foam arrestor bed of 218.0 kN (48,986 lb) occurs at 110.0 m (360.9 ft) from the EMAS entry. The static nose gear load for the B737-900 is 66.74 kN (14,998 lb) (Boeing 2013). Therefore, the maximum vertical strut force within the EMAS is 3.27 times greater than the static nose gear load. Assuming polytropic compression strut behaviour for these high and fast load cases within the EMAS, the strut should not be adversely affected, however should still be compared with the actual maximum design strut values. The actual maximum design strut value is not included, since it’s proprietary to the manufacturer.